Anti-NMDAR encephalitis with GFAPα IgG: a case report

Area of Science:

• Neuroimmunology
• Autoimmune Neurology

Background:

• Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis involves antibodies targeting NMDAR in the central nervous system (CNS).
• Glial fibrillary acidic protein (GFAP) astrocytopathy is another CNS autoimmune disease.
• The overlap between NMDAR antibodies and other autoantibodies against CNS targets remains understudied.

Observation:

• A 35-year-old male presented with symptoms mimicking anti-NMDAR encephalitis, including cognitive decline and psychiatric disturbances.
• Cerebrospinal fluid (CSF) analysis revealed pleocytosis and elevated protein levels, with positive tests for both NMDAR and GFAP antibodies.
• Brain imaging showed high-intensity lesions in various CNS regions.

Findings:

• The patient was diagnosed with autoimmune encephalitis, specifically anti-GFAP encephalitis, despite prominent anti-NMDAR encephalitis-like symptoms.
• This case highlights the potential for overlapping antibody positivity in autoimmune encephalitis.

Implications:

• Unusual presentations of anti-NMDAR encephalitis warrant testing for anti-GFAP antibodies.
• Early diagnosis and treatment with therapies like intravenous methylprednisolone can lead to positive outcomes in autoimmune encephalitis.
• Further research is needed to understand the clinical implications of co-occurring NMDAR and GFAP antibodies.